F1=m1a1 (nage - one who did the punch)
F2=m2a2 (uke - one who got launch)
F1 = F2
a1 is the one that's interesting. zero-inch punch = nage fist flat against uke body, no draw back any part of the body. this is one of the teacher tests, i believed.

I get there's no draw back or chambering, but there is still movement at the point where the strike begins (regardless of how much windup), right? In other words, there is still an accelleration of mass into the target mass, even though it starts from contact, right?
<sigh> I need to relearn physics. Why must we lose it if we don't use it? I was hoping my knowledge would age like wine, but each time I go back to retrieve a bottle it's missing. There seems to be some entity sucking it all up...and I hate to think of what it's been replaced with.
Mr. N. Tropy what have you done with my fine spirits?!